Ring-roll mill



5 Sheets-Shet 1 T. J. STURTEVANT RING ROLL MILL Filed Feb. 19,

112 V611 for:

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Dec. 10, 1929. T. J. SITURTEVANT i 1,739,437

RING ROLL MILL Filed Feb. 19. 1927 5 Sheets-Sheet 3 oooooooq I11 V612 for:

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T. J. STURTEVANT RING ROLL MILL 5 Sheets-Sheet 4 Filed Feb 19. 1927 I llllllllll' IIIIIIIIIIII bmwN IIIIIIII 1;

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Dec. 10, 1929. T. J; STURTEVANT 1,739,487

RING ROLL MILL Filed Feb. 19 1927 5 Sheets-Sheet 5 Patented Dec. 10, 1929 UNITED STATES PATENT orricr.

THOMAS J". ST'URTEVANT, OI" 'MSSKCHUSE'ETS, ESSIGNKD'R. TO STUETE- VANCE MILL mm, '01 ZBQSTON, A. CORPORATION OI" MASSA- 'CHUSETTS RING-ROLL MILL Application fil ed: February 19,1827. Serial No; 168,612.

The inventionto be. hereinafter described relates. to mills forcrushingv materials and more particularly tomills. of the roll ty e.

llhe purpose of the invention isto provide a mill which has. a number of improvedfeatitres contributing toward efiiciency in operation, durability and reduction in. the cost of construction. I g

.In. carrying the, invention into practical effect, the ring and rolls are enclosed in a casing com-prising abody and a. door which are formed. of. sheet metal, and a strong, heavy frame in the. form of a castingis mounted on and. secured to. the door, and servesto support the carriers forthe rolls and mechanism associated therewith, The construction is such that strains tending todistort the door are eliminated.

The rolls aremounted. on shafts on carriers, the latter having bearings for receiving the shafts which are. constructed to facilitate ready insertion of the shafts into.- said' hearings and their removalv therefromw Interposed betweenthe rolls and shafts are roller bearings having advantageous features. The rolls are the form. of castings and they are confined. against axial. movement onthe shafts by means including bolts which. extend through long-holes in the; rolls formed by cores when. the rolls are cast. Some of these holes are liable to be reduced or choked during casting thereof so that they will not be sufliciently large to allow the bolts-to pass therethrough. Therefore, each of the rolls is cast with agreater number of holes than bolts employed, so that. there. always willbe a sufiicient number thereof large enough to. allow the bolts to. pass therethrough without requiring the inconvenience and expense of boring the holes to bring them to the required size.

Three- --rolls are employed, theirarrangement being such: that gravity tends todraw the two lower rolls toward the ring and the upper roll from thering. I

The character. of theinvention will be best understood byreference. to the following descriptionof an embodiment thereof shown in the accompanying drawings, wherein:

. 1 is a side elevation of the mill;

Figs 2 is a vertical longitudinal section taken. on line 2.2 of Fig.1;

Fig. 3. is a plan. of the mill;

Fig; t is a. face view of the frame casting; 5 is. a section taken on line 55 of 6 Ba side view of the frame;

Fig- 7' is. a horizontal section taken on line 77 of'Fig..2-,

Fig. 8 on an enlarged scale is a. section thro ugh oneofthe rolls-and its carrier;

Fig. 9 on an enlarged scale is a section through a portion of the door;

Fig. 10 is a PGITSPGCtl-VQ view of one of the nels and extends downward, overlaps and is secured to the transverse channel 9 re ferred to.

Mounted upon the channels 13 are bearings 19 and2l in which is j ourn'alled' a horizontal shaft. 23- confined against movement axially thereof by collars 25 and 27 respectively engaging ends ;of the bearings 19- and 21. The shaft. 23 has .a portion which projects outward beyond the. bearing 19 and has fast thereon a large spur gear '29 driven by a pin ion 31; (Figs. 1 and on a countershaft 3'3 journalled in bearings 35 and 37 mounted on the. transverse/channels 7 and 9 of the bed. Faston the. conntershaft-isa pulley 39 adapted to. be driven from. any suitable source of power; The gear and pinion are enclosed in a protective housing 41. g

The shaft 23 projects outward beyond the bearing 21. and has fastthereon. a spider 43 carrying ananvil ring 45 having a transversely concaved crushing surface. The gear on one end of the shaft and the spider and ring on the other end of the shaft and the bearings for the shaft located intermediately of the gear and spider provide a desirable construction'having counterbalancing efiect which tends to reduce uneven Wear on the bearings.

The spider and ring are enclosed by a casing preferably formed of sheet steel and comprising a body 47 and a heavy sheet steel door plate 49 connected to the body by hinges 51. The construction is such that the door swings 011 a vertical axis. The back 53 of the casing is secured to the tranverse channel 11 and to ends of the channels 13. At the lower end of the'casing is an opening 55 through which the crushed material may be delivered. At the bottom of the casingand extending along the front side thereof is a member in the form of an angle bar 57 (Figs. 2 and 9). The lower edge of the door plate is spaced somewhat from said member to avoid friction therebetween when the door is swung to and from its closed position. To prevent dust from escaping through this space, an angle bar 59 is secured to the lower margin of the door and carries a strip 61 of felt or other suitable material. This construction is such that when the door is closed this strip will press against the upstanding fiange'of the angle bar 57 and prevent escape of dust through the space between the lower edge of thedoor and the angle 57.

The door supports the rolls, which cooperate with the ring in crushing materials, the construction being such that the door may be swung to open position and carry with it the rolls, thereby rendering the ring and the rolls readily and conveniently accessible for inspection and repair. To give the door the necessaryform to supoprt the mechanism carried thereby, it is provided with a frame in the form of a casting 68, (Figs. 2, 4, 5 and 6) having U-shaped arms 69, bearing portions 71 and bosses 73, said frame being se cured to the outer side of the sheet metal door by bolts 75 (Fig.1). y i

Carriers 77 (Figs. 1 and 8) have yokes 79 terminating in trunnions 81journalled in the bearings 71- These carriers project radially inward toward one another and are formed intermediate their ends to provide bearings 83. Shafts 85 are secured in these bearings and project between the sides of the arms and through apertures 87 in the sheet steel door, said apertures being sufficiently large to allow swinging movements of the shafts as more fully hereinafter described. The shafts project into the body of the casing and carry the rolls 89 within and cooperating with the anvil ring to crush materials fed between them.

Each carrier bearing 83 has a half round portion 89 (Fig. 8) and a half round portion 91, said portions being diametrically opposed and offset longitudinally of the shaft in the bearing. Also the bearing has a round portion 93 opposed to and spaced from the portion 89 and a round portion 97 opposed to and spaced from the portion 91. .Screws 99 and 101 are tapped into the bearing and may be adjusted to press the shaft into tight seating engagement with the round portions'89 and 91. The construction is such that in inserting the shaft into the bearing, it may be tilted somewhat with respect to the axis of the bearing and then the set screws may be set up to secure the shaft in the bearing. On the other hand, in removing the shaft from the bearing, the set screws are released and again the shaft may be tilted somewhat with respect to the axis of the bearing so as to be freely and readily withdrawn therefrom. y

The shafts have enlarged portions 103 which experience the greatest strain. Projecting out beyond the enlarged portions are smallerportions 105 on which the rolls 89 are mounted. Each of these rolls is a chilled casting having 'several'bolt receiving holes 107 (Figs. 8 and 11) therein. In the -pres- I ent instance, each roll has six of these holes formed by cores in'casting the rolls, although merely three holes are required for the bolts. It is found in practice that in casting'a roll, some of the holes are liable to be contracted or clogged so that they are too small to allow the bolts to pass 'therethrough, but a per centage of the holes can be relied upon to come through the casting process and be sufficiently large to receive the bolts without the expense and inconvenience of boring them.

Hyatt roller bearings are provided between each roll and its shaft. In the present instance, two sets 109 and 111 of these bearings are employed and disposed in axial alinement. Each set comprises a cage 113 (Fig. 10), rollers 115, and a bushing or race 117 which is rolled to form and has ends meeting on a wide V-li'ne 119. Each of the rollers 115 is formed of a helically wound strip. The rollers are circumferentially distributed, and are positioned by the cage between the shaft and the race 117.. .The con-' struction is such that the rollers may revolve about the shaft and rotate on their own axes and desirably reduce the friction between the parts and distribute the wear thereon. Also, the cages including the races 117 may creep relatively to the roll, thereby further to reduce the wear. The ro'lls experience heavy duty and rock in "and out relatively to the ring with hammer-like action. The helically wound strip rollers are advantageous under this condition since they can yield'to allow relief from shocks received by ment with the shaft and raceways with relation to the shaft and tend to work endwise or burrow. In so doing they assume a slightly spiral form which concen trates the bearing and wear on some of the convolutions of such rollers, but by having two sets of the roller bearings, rollers in a line in the two sets may be relied upon to have convolutions in adequate bearing engageat all times.

To confine the rollers against movements longitudinally of the shafts and to protect the bearin 's from dust, each roll may be provided with washers 121 and 123 at opposite ends thereof. The washer 121 is formed of two parts 125 and 127 (Fig. 11), the Washer 121 being received by a groove 129 (Fig. 8) adjacent the end of the shaft. A cupshaped cap 131 covers the end ofthe shaft and receives theparts of the washer 121. The washers and the cap have registering holes therein and through bolts 133 pass through these holes and through certain of the holes 107 of the roll, thereby to hold'the parts in assembled relation. The washer 123 has a sleeve 135 projecting therefrom and entered into an annular groove 137 in the bearing 83, and the washer 123 has an annular groove 139. The construction is such that the annular grooves 137 and 139 and the space between the sleeve 135 and the shaft may be filled with grease and prevent dust from reaching the roller bearings.

A suitable lubricant receiving cup 1 10 (Fig. 1) may be attached to the outer end of the shaft and lubricant may be conducted therefrom through a duct- 141 to the roller bearings. This duct has a portion 143 which is reduced at the enlarged portion 103 of the shaft to facilitate boring of the duct and to avoid weakening the enlarged portion of the shaft. 7 p

Mounted on the sleeves 135 are slides 1 15 (Fig. 2) interposed between collars 147 and the door and urged toward the door by spring-pressed bolts 149. The door apertures 87 are somewhat larger than the sleeves 135 and allow rocking movements of the shafts and rolls. The slides prevent escape of dust from thecasing through the door apertures.

' The roll shaft carriers 77,referred to, entend radially inward and have portions 151 opposed to a disk 153 (Fig. 2), balljoints 155 being interposed between said carrier portions and disk. A screwor element 157 is carried by a spider 159 and has its inner end engaging a recess in the disk. This screw acts as a fulcrum point for the disk. It may be adjusted relatively to the spider as required and may be secured by suitable nuts.

The spider is formed to provide bosses 161 registering with the frame bosses 73, referred to. Rods or bolts 163 extend through the frame and spider bosses and upper roll away from the ring.

throughholes in the sheet metal door, said bolts having suitable nuts at opposite ends thereof. A large coil spring 165 and a small coil spring 167 encircle each of the rods and are confined between a spider boss and a cap 169 on the rod.

The rolls may be set into engagement with the anvil ring, the spider bosses may be brought into engagement with the frame bosses, and the tension of the springs may be be properly adapted. -When materials to be crushed come between the rolls and the ring, the rolls will be caused to rock radially inward, thereby causing their carriers to swing on their trunnions and cause the inwardly extending portions 151 of the carriers to press outward against the disk 153. This pressure in turn will be transmitted by the screw 157 to the spider, and this pressure will be resisted by the coil springs.

As stated, gravity tends to hold the two lower rolls against the ring and to draw the Suitable means may be provided to neutralize the pressure of the two lower rolls on the ring due to their weight. To accomplish this, in the present instance, the upper carrier is provided with an arm 171 (Figs. 1 and 2) which projects up therefrom, and secured to the upper margin of the door is a bracket 17 3. A yoke 175 (Fig. 7 receives the arm 171, has legs extending beneath the bracket 173 and through holes in a cap 177 engaging adjusting nuts 179 secured by lock nuts 181. A coil spring 183 is confined between the end of the bracket and the cap. The tension of the coil spring may be adjusted so that the upper roll will be held up to the ring with a pressure Sll'fllClGDt to neutralize the downward pressure of the lower rolls on the ring due to their weight. This will avoid strain which otherwise would come on the shaft 23 carrying the ring and spider.

The frame 63, referred to, is cast to provide a chute 185 (Figs. 1, 5, 6 and 7) which registers with a spout 187 fastened to the inner side of the door, and is suitably formed to conduct the material to the space between one of the rolls and the ring. A chute section 189 (Fig. 1) is secured to the door and communicates with the chute 185. A suitable hopper may be provided above the chute for feeding materials into the mill.

The door is secured normally in closed position by bolts 191 (Fig. 1). When it is desired to swing the door to open position for access to the rolls and other parts carried by the door or in the casing, the bolts 191 are be readily swung to open and closed positions.

In'operation, the shaft 23, the spider and anvil ring are rotated. The materials are fed into the mill and cling to the ring under the influence of centrifugal force. The rolls will progressively act upon and crush the materials. In so doing the rolls will be rocked away from the ring and their pressures will be equalized by the portions of their carriers which press against the disk which is fulcrumed on the screw carried by the spider.

The heavy steel plate of the door is strong in tension and capable of carrying the heavy rolls, theircarriers and other parts associated therewith; while the frame casting is strong in compression and capable of withstanding crushing stresses, the resultant lines of force of which extend inward in diagonal lines from the points of contact of the rolls with the ring, to the fulcrum element engaged by the disk; thereby setting up compression stresses in the arms of the frame casting'which are ably resisted by the latter.

The bed formed of the arrangement of channels described enables the large spur gear to be mounted on an end portion of the shaft well toward the floor. The longitudinal channels may have strong deep webs, bringing the shorter longitudinal channels up near to the shaft so that they serve effectively to support the shaft bearings, the shaft and the heavy parts carried thereby, and give the structure the stiffness and rigidity required.

It will be understood that the invention is not limited to the specific embodiment shown, and that various deviations may be made therefrom without departing from the spirit and scope of the appended claims.

' What is claimed is:

1. A crushing mill comprising, in combination, a shaft, an anvil ring carried by the shaft, rolls within and opposed to the ring for crushing materials, a casing for the ring and rolls comprising a body and a steel plate door having apertures therein, a frame in the form of a unitary casting mounted on and secured to the door and formed with U-shaped arms having spaces between said arms over said apertures, each of said arms having a pair of bearings, carriers having trunnions mounted in said bearings, and shafts'on said carriers carrying the rolls and projecting through said spaces and door apertures into the casing body.

2. A crushing mill comprising, in combination, a shaft, an anvil ring carried by said shaft, rolls cooperating with the ring for crushing materials, a casing for the ring and rolls comprising a body and a steel plate door having apertures therein, a frame in the form of a unitary casting mounted on and secured to the outer side of the door and formed with arms provided with bearings, carriers having trunnions mounted in said bearings, and shafts on said carriers carrying the rolls and projecting through the door apertures into the casing body.

3. A orushing mill comprising, in combination, a shaft, an anvil ring carried by said shaft, rolls cooperating with'the ring for crushing materials, a casing for the ring and rolls comprising a body and a steel plate door having apertures therein, a frame mounted on and secured to the outer side of the door and provided with bearings, carriers having trunnions mounted in said bearings, said carriers having bearings, and shafts carrying the rollsand mounted in the carrier bearings and projecting through the door apertures into the casing body, each of said carrier bearings having half-round portions diametrically opposed and offset longitudinally of and engaging the shaft, for facilitatinginsertion of the shafts into and removal from the carrier bearings.

4. A crushing mill comprising, in combination, a shaft, an anvil ring carried by the shaft, rolls within and opposed to the ring, a casing for the ring and rolls comprising a body and a steel plate door having apertures therein, a frame in the form of a unitary casting mounted on and securedto the door and having arms with bearing port-ions, said casting being formed to provide a passage for conducting materials into the casing, carriers pivotally mounted in said bearing portions, and shafts securedcto the carriers and projecting through the arms and the door apertures into the body of the casing and carrying the rolls.

5. A crushing mill comprising, in combination, a shaft, an anvil ring carried by the shaft, a casing for the ringcomprising a body and a door having apertures therein, carriers mounted on the door, shafts on the carriers extending through the door apertures into the body of the casing, rolls on the shafts, washers at opposite ends of the rolls, and through bolts extending through holes in the rolls and washers.

6. A crushing mill comprising, in combination, an anvil ring, said ring for crushing materials, shafts car rying said rolls and means. for preventing the rolls from moving longitudinally of their shafts comprising washers at opposite ends of each roll, holes in the washers and roll,

' and through bolts entered through said holes.

7 A crushing mill comprising, in combination, a shaft, an anvil ring carried by the shaft, rolls within and opposed to the ring forcrushing materials, a casing for the ring and rolls comprising a body and a steel plate door having apertures therein, a frame in the form of a single casting mounted on and secured to the door and having bosses and bearing portions cast integral therewith, carriers pivotally mounted in said bearing por tions, shafts on the carriers projecting rolls cooperating with through the door apertures into the casing body and carrying said rolls, said door having holes registering with the frame bosses, a spider having bosses registering with the frame bosses, bolts extending through the door holes and frame and spider bosses, caps on said bolts, coil springs encircling the bolts and confined between the spider bosses and the caps, a disk opposed to inwardly projecting port-ions of the carriers, and a fulcrum element on the spider engaging the disk.

8. A crushing mill comprising, in combination, a bed having longitudinal channels, transverse channels mounted on the longitudinal channels, channels shorter than the longitudinal channels extending between and secured to the transverse channels, bearings mounted on the shorter channels, a shaft journalled in said bearings and having end portions projecting beyond said bearings, a gear on one of said end portions and a spider on the other end portion of said shaft, an anvil ring on the spider, a casing secured to said bed and enclosing the spider and ring, and rolls mounted on the casing and cooperative with said ring to crush materials fed between them.

THOMAS J. STURTEVANT. 

